package com.example.competitionregistration.util;

import java.io.Serializable;
import java.security.MessageDigest;

/**
 * @Author QuanJingFang
 * @Description //TODO SHA1加密工具类
 * @Date 2023/7/17 20:58
 **/
public class SHA1Util implements Serializable{
    private static final long serialVersionUID = 1L;

    public static String SHA1(String str){
        if(str == null || str.length()==0){
            return null;
        }
        char hexDigits[]={'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'};

        try {
            MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
            mdTemp.update(str.getBytes("UTF-8"));

            byte[] md = mdTemp.digest();
            int j = md.length;
            char buf[] = new char[j*2];
            int k = 0;
            for(int i=0;i<j;i++){
                byte byte0 = md[i];
                buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
                buf[k++] = hexDigits[byte0 & 0xf];
            }
            return new String(buf);
        } catch (Exception e) {
            return null;
        }
    }
}
